Regulating system



FeBL B, 1942. o. SCHARPF REGULATING SYSTEM Filed Jul 31, 1940 -2Sheets-Sheet 1 MAM/Ale 19 52 To OTHER,

Pl LOTS MA/IV A/B 3nnentor (Ittornegs Patented Feb. 3, 1942 UNI TEDs'rl' rrasv PATENT OFF C 7 2,272,025, I v REGULA TING SYSTEM OttoScharpi, Milwaukee, Wis, assignor to, Johnson Service Company,Milwaukee, Wis.,' a cor- .poration of Wisconsin Application July 31,1941}, Serial No. 348,917 (c1. ass-+1) 10 Qiaims. This invention relatesto regulating systems and especially to regulating systems of thepneumatic type. It is concerned with the control of such systems so asto permit different types of response without disturbing the adjustmentor characteristics of aprimary controlling. instru- 'ment. i.

In the art of automatic temperature and humidity control, two classes ofinstruments are well knowmnamely, class 1 instruments in which branchline pressure increases with temperature increase, as in the control ofa heating medium,

., and class 2 instruments in. which the branch line pressuredecreasesas temperature increases, as in the control of a coolingmedium.It is desirable in systems of the general type mentioned above tosimplify the apparatus as much as possible, and particularly toprovidejmeans for changing from class 1 to class 2 or vice versa,

without disturbing the adjustment of the temperature or otheratmospheric condition responsive instrument. Y It has been consideredaxiomatic in the art heretofore that change fromone class of instru mentto the other necessitated reversal of the operation of the atmosphericcondition responsive instrument. Such reversal was'objectionable becauseit necessitated changes in the setting of a delicate instrument andundue conipli' cation of the same. In a large system in which athermostat or the like is located in each room,

in a directionopposed to its spring bias, or in the same direction asits springbias. Accordingly, the main objectof thepresent invention isto provide apneumatic regulatingsy'stem in which a pilot valve may be.causedto operate at will as a class 1 ora class 2 instrumentfor'controlling the supply of a heating or cooling medium whileemploying anordinary non-reversible control instrument. Aiurther objectof-the invention is toprovide anarrangement in which a pressure'operatedpilo'tvalve may belcaused to respond to branch line pressure increase soas to actuate the heat exchange medium control in thesame direction asthat to which it is biased. For'purposes oi illustration the inventionhas been described as applied to the pilot valve of a pneumatic systemin which the valve for the control or heat exchange medium .ismoved inthe problem becomes amplified. The present invention is concerned withmeans,- entirely independent of the controlling instrument, for shiftingfrom one class to the other, asin changing from a heating to a coolingcycle or vice versa,

usinga standard class 1 thermostathumidostat, or the like.

Where 'a valve, a damper, or a similar means is employed to control theflow of a heating or a cooling medium, it is usual to bias the valve orthe like in one direction by a spring and to move it positively in theother direction by pneumatic pressure subject to control byanatmospheric condition responsive instrument'such as a thermostat. Withsuch an arrangement the spring can be made to bias the'valve or the liketo either closed or open position, butit is impossible, with prior artapparatus. to change the direction of response of the valve withoutrevcrsing the action of the thermostat.

The present invention provides means whereby a valve or the like forcontrolling the flow'of a heat exchange medium may be caused ,uponincrease in branch line pressure to move either onedirection by pressurebuilt up in a diaphragm chamber, and in the opposite] direction by anactuating spring. It is tobe understood, however, that the. invention isnot limited to use ports, the control valve being positioned forclass 1operation; and

Fig. 3 is a detail sectional view of the control valve of Fig. 2,showingthelvalve positioned for class 2 operation of the system.

The system illustrated in Fig. 1' comprises a pressure or diaphragmmotor M for operating a valve to control flow of heat exchange medium,

a control instrument '1', anda pilot valve 'V for coordinating theoperation of the motor and instrument.

The motor Mcomprises a diaphragm H and a. diaphragmchamber I4 supplied.with pressure fluid through line l5.

1 Bearingagainstthe diaphragm is a plate 9 supporting a valve stem 8 anda spring seat l8 carry-' ing biasing spring ll. This springopposespressure in the diaphragm chamber to control movement of valve 5 inthemedium supply line I.

' The control instru'ment'T is a standard nonreversiblethermostat of thevtype disclosed in Otto Patent 1,500,260( It f'co'mp'rises a body 28 acasing l2 containing containing three chambers 29, 3| and 32, formed bydiaphragms 33 and 34 and cap 35. Main air from a supply line |9 (usuallyat lbs. pressure may be supplied to the small chamber 29 associated withsmall diaphragm 33, through a combined admission and exhaust valve 42,and also through a pin valve 36 to the chamber 32. Leak port 31connected to chamber 32 is controlled by lid 38 in response tobi-metallic member 39 adjustably supported by the usual pivoted,weighted saddle 4| and adjusting screw structure 40. Combined admissionand exhaust valve 42 is biased to the left by a spring 43 and may engagea seat 41 to control pressure in chamber 29. Valve 42 also cooperateswith an opening 44 in a hub 45 connecting the two diaphragms 34 and 33to control the pressure in chamber 29. The chamber 3| between the twodiaphragms is vented to atmosphere as at 46. from pipe I9 is supplied tothe thermostat, the pressure built up in chamber 32 is determined by theposition of leak port lid 38.

When the lid 38 closes leak port 31, pressure builds up in chamber 32,and diaphragm 34 moves to the right closing the exhaust duct 44 byengaging the valve 42 and moving this valve away from seat 41.Therefore, main line pressure enters chamber 28 and is fed to branchline 5|. When, however, lid 38 opens port 31 and vents the chamber 32,spring 43 moves the valve 42 to seating position at 41 so that pressurein chamber 29 is dissipated through duct 44 and vents 46 in chamber 3|.The net result of this arrangement is to cause pressure variations inchamber 29, and hence in branch pipe 5|, in response to variations inthe position of thermostat 39 controlling leak port lid 38.

In the usual arrangement of a class 1 instrument, temperature increaseproduces an increase in branch line pressure to reduce the rate of flowof heating medium or increase the rate of flow of cooling medium. Forreversible control, two thermostats reversely arranged were required, orif a single thermostat be used its action must be reversible. Thepresent arrangement makes it possible to reverse the control at willusing a single non-reversible thermostat. It involves the use of areversible pilot valve, such as valve V, which will now be described.

This valve comprises a hollow body 53 attached to casing l2 at 54. Thisbody houses the pilot valve mechanism consisting of a leak port, dia--phragm means for controlling the leak port, means permitting reversal ofthe operating characteristics of the valve, and follow-up mechanism forcoordinating the movements of the valve 5 and the leak port control.Considered in detail, the floor of the body 53 contains a duct 24forminga continuation of pipe I5 and supplied from main air line 2|through filter 22 and pin valve 23. A leak port 25 in the floor ofchamber 53 controls pressure discharge from duct 24. -Upstanding fromthe floor of body 53 and surrounding the leak port 25 is a guide tube 55for leak valve 26. This valve is adapted to be moved with reference toleak port 25 b certain diaphragm structure about to be described. Thechamber surrounding the leak port is vented to atmosphere at 58.

The cap 58 carries a set of spacer discs with When pressure class 1 orclass 2 operation. A small diaphragm 16 is used to avoid the use of apacking gland and engages head 6| on stem 62 (hereinafter described). Asecond small diaphragm 85 is attached to the center of main diaphragm 84by a ported hub 83, forming a diiferential diaphragm chamber 82 in whichrising pressure urges the diaphragm assembly, and consequently the hub83, upward. Chamber 8| formed above diaphragm 86 and chamber 82 are bothconnected to branch line 5|. Rising pressure in chamber 8| urgesdiaphragm 86 downward. Thus the two diaphragm units operate in reversedirections in response to the same change of branch line pressure. Avalve operating rod 19 is attached to upper diaphragm 86 and is freelymovable through hub 83 to engage diaphragm 76 and thus react on head 6|.Chambers 88 and 89 formed between the main diaphragms 84 and 86 andconnected at all times through the opening in partition 11 are bothconnected to line 8'1. Line 81 is connected by a valve 52 either to mainline I9 or to atmosphere. Main line pressure is always higher andatmospheric pressure always lower than pressure in branch line 5| andthus is always eifective in chambers 8| and 82. Hence when valve 52 isin venting position, hub 83 is forced upward to an inactive position anddiaphragm 86 takes control, giving class 1 response, whereas when valve52 is set to admit main line pressure diaphragm 86 is forced upward toinactive position and diaphragm 84 takes control through reaction of hub83 downward upon diaphragm I6 and head 6|.

The cap 58, which carries the above described diaphragm assembly, isthreaded into the body 53 at 51. The cap 58 is recessed on'its lowerside as indicated at 59 to define the upper position of the head 6| onvalve operating stem 62. The head 6| acts also as a seat for the upperend of the loading spring 58. The Valve 26 previously described ismounted in the lower end of a tubular member 83 axially alined with thestem 82 and guided within tubular guide55. The stem 62 carries a head 68which is slidable in the upper end of the tubular member and whichreacts downward upon the tubular member through a spring 64. Separationof the parts is prevented by a screw 65 which is threaded into themember and whose head acts as a limit stop to limit the separatingmovement of the tubular member and the stem 62. Thus the spring 64limits the force with which the valve 26 may be seated and the screw 65assures precise timing of the opening movement of the valve 26.

Slidably mounted on the exterior of the tubular guide 55 is a sleeve 66having a flange 61 which serves as a lower seat for loading spring 56.Sleeve 66 is externally threaded to receive a stop-ring 68 withcooperating locking ring 69. The stop-ring 68 is in operative engagementwith the forked ends of a lever 1| extending through opening I6 incasing l2. This lever is pivoted at 12 and adjustably connected througha pinand-slot connect-ion 13 with a block 14 carried by the valve stem8. Adjustment of screw 15 by placing it in difierent openings in block14 makes it possible to vary the motion ratio between the movements ofvalve stem 8 and the stop ring 68. Hence the loading exerted by spring56 is determined by the position of valve 5.

In describing the operation of the mechanism disclosed it will first bepointed out how operation takes place during the heating cycle (class 1operation), that is, with the valve 52 in its full chambers 93 and 94.

line or Winter position venting line 81 and chambers 88 and 89 toatmosphere. It will be assumed that main air pressure, of fifteen poundsper square inch, is supplied to pipe I9, and that ambient temperatureconditions are such. that line I is vented and valve 5 opened. Iftemperature conditions change to cause a rise in pressure in branch line5|, valve 5 will be closed gradually. Leak port 25 will be closed bypressure in chamber 8|, moving rod I9 downwardly, stressing spring 58,and building up pressure in diaphragm chamber I4 to operate the valve 5,while branch pressure in chamber 82 holds hub 83 inactive. Movement ofthe valve stem 8 will be opposed by spring II until a balance isobtained. Hence, increase in branch pressure will move valve stem 8downward, while a decrease in branch pressure will move the stem upward.Therefore, with switch 52 in Winter position, increase in branchpressure will close valve 5 and grit off the flow of heating medium(class 1 operaion).

When thevalve 52 is in dotted line or Summer position, that is during acooling cycle (class 2 operation), main line pressure is established inline 81 and chambers 88 and 89. Pressure under diaphragm 88 holds rod 19against the top of casing 58 to render it ineffective to control theleak port. The position of valve 28 will therefore be determined by theratio of combined branch pressure in main chamber 82 and force of spring56 to opposing supply pressure in chamber 89. Pilot spring 58 ispreferably of such characteristics that when it is fully compressed bythe closure of valve 5 it exerts slightly less force than that exertedby supply pressure from line 8'! acting against diaphragm 84. Hence,

through opening 91 93 controls leak port 9I for class 1 operation; henceit corresponds to chamber 8I of Fig. 1. Diaphragm, chamber 94 controlsleak port 92 for class 2 operation, and hence corresponds to chamber 82of Fig. 1. A change-over valve 95 takes the placeof valve 52 of Fig. 1.The parts are so arranged that with valve 95 in the position of Fig. 2,pressure' from line I03 is'vented in valve 95, pipe 98 is blanked, andbranch line pressure in line 98 is supplied through pipe 99,to diaphragmchamber 93. Increase in pressure in this chamber closes the lid IOI ofleak port 9I to buildup pressure in line I02, and hence in diaphragmchamber I4a to close valve 5a. Since diaphragm chamber 94 is ventedthrough line'jI03 and port 91 in valve 95, leak port 92 remains closedand valve 5a is controlled solely by leak port 9|. A diaphragm loadingspring I04 reacts between one endof lever I05 and the diaphragm ofchamber 93.

Lever I05 is adjustably "connected to'the ,valve stem 8a in a similarmanner and performs. the same follow-up function as lever II previouslydescribed in connection with Fig. l.

' Leak port. 92 has a lid I06 biased to'closed position by a spring I 01and adjustable by screw I08. The diaphragm of chamber 94 is loaded byspring I09 whichengages follow-up lever III. Lid I06 of leak port 9'2 isactuated by rodv H2.

as a class 1 instrument in which increase in temperature increasesbranch line pressure, and

valve stem 8 may move through its full. stroke,

and leak port 25 be closed when branch line 5I and chamber 82 are atatmospheric pressure.

The pilot valve action is therefore reversed solely by a movement of thevalve 52 from one midity, wet bulb temperature, dry bulb tempera v ture,or the like. In the drawings, the control line 81 with its valve 52, isshown connected to a single pilot valve. Obviously this line can beusedto control simultaneously the operation of a plurality of pilotvalves so that their operating characteristics may be reversedsimultaneously by movement of the single valve. When the device of thepresent invention is applied to the simultaneous control of severalpilot valves, the line 8'! controlled by valve 52 will be extended asindicated at 90, and each additional pilot valve will operate in themanner already described in connectionwith the pilot valve shown.

pressure increase inchamber Md moves the valve 5a in opposition toits'spring. bias. I

Fig. 3 shows the change-over valve 95 positioned. for reverse operationas in a class 2 instrument, that is, increase in branch line pressurefrom instrument T will cause movement of valve 511 in an openingdirection, and in the direction of its spring bias. When the valve 95isin the position of Fig. 3, main linepressure from line chamber 94 andcontrollingthe pressure therein.

Increase of pressure in this diaphragm chamber opens the lid I08 ofleakport 92 to reduce the so that the amount of movement of valvef5a isAn alternative embodiment of the. principles connection similar to lever'II of Fig. 1.

In Fig. 2 the pilot device V includes two leak ports SI and. 92, thelids of which are subject to control by the pressure intwo diaphragmHere diaphragm chamber outfurther explanation.

determined by the amount of venting-accomplished by the particular leakport which is exercising control. As a class 1 instrument with the valvein the position of Fig.2, the control function is exercised by leak port9I, while lid I06 of leak port 92 is held closed by spring I01.

As a class 2 instrument with the valve 95in the position of Fig. 3, thecontrol is :exercised' by leak port 92, while mainline pressure inchamber 93 holds the lid IOI ofleak port 9I closed.

The details of operation of the mechanism shownin Figs. 2 and3 will beunderstood withadvantages that have been set forth in connection withthe apparatus of Fig. 1 with the added advantage of simplification.

twoembodiments of which are illustrated. I The principle of the presentinvention is not limited to the particular arrangement shown, but may beapplied to other forms of fluid pressure responsive apparatus where itis desired Through 1 It presents thesame' It indicates the genericnature of the present invention, only to reverse the operatingcharacteristics of one or more elements of the system from a centralpoint without adjustment or alteration of the temperature responsive orequivalent responsive instrument. Consequently, the claims are to beconstrued broadly and without limitation to the particular type ofapparatus shown.

What is claimed is:

1. In an automatic controlling system for a heat exchange medium and inwhich the parts are arranged to operate in either a heating or a coolingcycle; a non-reversible thermostatic means; a source of heat exchangemedium; a valve for controlling the flow of such medium; a source ofpressure fluid; a pressure motor for operating said valve; meanscomprising a leak valve responsive to conditions established by saidthermostatic means for controlling the flow of fluid from said source tosaid motor; a follow-up connection between said leak valve and saidmedium control valve; and means acting on said leak valve to change theoperation of the medium control valve from one cycle to the other.

In an automatic controlling system for a heat exchange medium and inwhich the parts are arranged to operate in either a heating or a coolingcycle; a non-reversible thermostatic means; a source of heat exchangemedium; a valve for controlling the flow of such medium; a source ofpressure fluid; a pressure motor for operating said valve; a leak valvefor controlling the supply of fluid from said source to said motor;diaphragm means responsive to conditions established by saidthermostatic means for controlling said leak valve; a follow-upconnection between said leak valve and said medium control valve; andmanually operable means for supplying pressure to and exhausting it fromthe diaphragm means to change. the operating cycle of said mediumcontrol valve.

3. In an automatic controlling system for a heat exchange medium and inwhich the parts are arranged to operate in either a heating or a coolingcycle; a valve for the control of the meoium; pressure responsive means"for operating the valve; atmospheric condition responsive means forcontrolling the pressure responsive means; a pilot valve interposedbetween the atmospheric condition responsive means and the pressureresponsive means; a follow-up connection between said medium controlvalve and said pilot valve; and means operating independently of theatmospheric condition responsive means for changing the response of saidpilot valve from one cycle to the other.

4. In an automatic controlling system for a heat exchange medium and .inwhich the parts are arranged to operate in either a heating or a coolingcycle; a valve for the control of the medium; pressure responsive meansfor operating the valve; atmospheric condition responsive means forcontrolling the pressure responsive means; a pilot valve including aleak port interposed between the atmospheric condition responsive meansand the pressure responsive means; diaphragm means in said pilot valvefor controlling sltid leak port in accordance with the operation 01 theatmospheric condition responsive means; and means including a follow-upconnection between the medium control valve and the leak portcontrolling means for reversing the direction of response of said pilotvalve to change the operation of the medium control valve from one cycleto the other.

5. In an automatic controlling system for a heat exchange medium inwhich the parts are arranged to operate in either a heating or a coolingcycle; a valve for the control of the medium; a pressure motor foroperating the valve; atmospheric condition responsive means forcontrolling said pressure motor; a pilot valve interposed between saidatmospheric condition responsive means and said pressure motor, saidpilot valve including a leak port; and pressure responsive diaphragmmeans in said pilot valve for reversing the character of the responsesof said leak port to pressure variation, to change the operation of themedium control valve from one cycle to the other.

6. In an automatic controlling system for a heat exchange medium inwhich the parts are arranged to operate in either a heating or a coolingcycle; a valve for the control of the medium; a pressure motor foroperating the valve; atmospheric condition responsive means forcontrolling said pressure motor; a pilot valve interposed between saidatmospheric condition responsive means and said pressure motor, saidvalve including leak port means; pressure responsive means comprising aplurality of diaphragms for controlling said leak port means; and meansoperable at will for applying pressure to certain of said diaphragms toreverse the direction of response of the leak port controlling meanswith respect to the atmospheric condition responsive means, to changethe operation of the medium control valve from one cycle to the other.

'7. In an automatic controlling system for a heat exchange medium inwhich the parts are arranged to operate in either a heating or a coolingcycle; a valve for the control of the medium; a pressure motor foroperating the valve; atmospheric condition responsive means forcontrolling sai dp egsure motor; a pilot valve interposed betweeriznsaid atmospheric condition responsive means and said pressure motor, saidvalve including leak port means; a first diaphragm means controlled bysaid atmospheric condition responsive means for controlling said leakport means during one of said cycles; a second diaphragm meanscontrolled by said atmospheric condition responsive means forcontrolling said leak port means during the other of said cycles; andmanually operable means for selectively rendering either of saiddiaphragm means ineffective.

8. In an automatic controlling system for a heat exchange medium and inwhich the parts are arranged to operate in either a heating or a coolingcycle; a valve for the control of the medium; pressure responsive meansfor operating the valve; atmospheric condition responsive means forcontrolling the pressure responsive means; a pilot valve interposedbetween the atmospheric condition responsive means and the fluid; leakport means in said pilot valve; a first diaphragm operated means in saidpilot valve for controlling said leak port means in response to saidatmospheric condition responsive means; and a second diaphragm operatedmeans responsive to receipt of pressure fluid from said source forrendering said first diaphragm operated means ineffective.

9. In a system for regulating the flow of heat exchange medium, a sourceof medium; valve means for controlling the flow of said medium; meansfor biasing said valve means in one direction by an amount proportionalto the extent of movement of the valve means; a source of pressurefluid; fluid pressure operated means for actuating the valve means inopposition to its bias; pilot valve means including a leak port arrangedto be controlled by a regulating pressure; pressure regulating meansresponsive to an atmospheric condition and controlling the pilot valvemeans; follow-up mechanism for coordinating the movements of said mediumcontrol I valve with the pilot valve means; and means for reversing theaction of said pilot valve means relatively to said pressure regulatingmeans.

10. In a system for regulating the flow of a heat exchange medium; asource of heat exchange medium; valve means for controlling the flow ofsaid medium; means for biasing said means; a source of pressure valvemeans toward one. limiting position by an amount proportional to itsdisplacement therefrom; a pressure motor for opposing said biasing fluidconnected with said pressure motor; pressure actuated pilot valve meansfor controlling said pressure motor, means responsive to changes in anatmospheric condition for controlling the pressure which controls saidpilot valve means; follow-up mechanism for coordinating the movements orsaid medium control valve and said pilot valve means; and means .forreversing the action of said means responsive to changes in atmosphericcondition upon said pilot .valve means.

' OI'IO SCHARPF.

